Abstract

The reduced divergence angle of the photonic crystal vertical-cavity surface-emitting laser (PC-VCSEL) was investigated in both theory and experiment. The photonic crystal waveguide possessed the weakly guiding waveguidecharacteristic, which accounted for the reduction of the divergence angle. The three-dimensional finite-difference time-domain method was used to simulate the designed PC-VCSEL, and a calculated divergence angle of 5.2° was obtained. The measured divergence angles of our fabricated PC-VCSEL were between 5.1° and 5.5° over the entire drive current range, consistent with the numerical results. This is the lowest divergence angle of the fabricated PC-VCSEL ever reported.

Received 04 December 2008Accepted 25 April 2009Published online 14 May 2009

Acknowledgments:

This work is supported by the Chinese National Key Basic Research Special Fund/CNKBRSF (Grant No. 2006CB921700), the National Natural Science Foundation of China (Grant Nos. 10634080, 60677046, and 60838003), and the National High Technology Research and Development Program of China (Grant No. 2006AA03Z403).